/*
 * Copyright (C) 2009, Edmundo Albuquerque de Souza e Silva.
 *
 * This file may be distributed under the terms of the Q Public License
 * as defined by Trolltech AS of Norway and appearing in the file
 * LICENSE.QPL included in the packaging of this file.
 *
 * THIS FILE IS PROVIDED AS IS WITH NO WARRANTY OF ANY KIND, INCLUDING
 * THE WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL,
 * INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
 * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
 * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
 * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 */

package javax.media;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.Vector;
import java.util.logging.Level;
import java.util.logging.Logger;

import net.sf.fmj.utility.LoggerSingleton;

/**

 *
 */
public class PlugInManager
{
	// This class is expected to route all calls (using reflection) to javax.media.pim.PlugInManager, see the JavaDoc.
	// We'll do the same, to ensure maximum compatibility, although the reasons for this technique are not clear.
	// I suspect that they did this to make it easier to ship "performance packs" for different operating systems, which might
	// have different implementations for these various managers.

	private static final Logger logger = LoggerSingleton.logger;

	
	public static final int DEMULTIPLEXER = 1;

	public static final int CODEC = 2;

	public static final int EFFECT = 3;

	public static final int RENDERER = 4;

	public static final int MULTIPLEXER = 5;

	
	private static Class implClass;
	private static Method getPlugInListMethod;
	private static Method setPlugInListMethod;
	private static Method commitMethod;
	private static Method addPlugInMethod;
	private static Method removePlugInMethod;
	private static Method getSupportedInputFormatsMethod;	
	private static Method getSupportedOutputFormatsMethod;	
	
	private static Method getStaticMethodOnImplClass(String name, Class[] args, Class returnType) throws Exception
	{
		final Method m = implClass.getMethod(name, args);
		if (m.getReturnType() != returnType)
			throw new Exception("Expected return type of method " + name + " to be " + returnType + ", was " + m.getReturnType());
		if (!Modifier.isStatic(m.getModifiers()))
			throw new Exception("Expected method " + name + " to be static");
		return m;
	}
	
	private static synchronized boolean init()
	{
		if (implClass != null)
			return true;	// already initialized;
		
		
		try
		{
			implClass = Class.forName("javax.media.pim.PlugInManager");
			if (!(PlugInManager.class.isAssignableFrom(implClass)))
				throw new Exception("javax.media.pim.PlugInManager not subclass of " + PlugInManager.class.getName());
			getPlugInListMethod = getStaticMethodOnImplClass("getPlugInList", new Class[]{Format.class, Format.class, int.class}, Vector.class);
			setPlugInListMethod = getStaticMethodOnImplClass("setPlugInList", new Class[]{Vector.class, int.class}, void.class);
			commitMethod = getStaticMethodOnImplClass("commit", new Class[]{}, void.class);
			addPlugInMethod = getStaticMethodOnImplClass("addPlugIn", new Class[]{String.class, Format[].class, Format[].class, int.class}, boolean.class);
			removePlugInMethod = getStaticMethodOnImplClass("removePlugIn", new Class[]{String.class, int.class}, boolean.class);
			getSupportedInputFormatsMethod = getStaticMethodOnImplClass("getSupportedInputFormats", new Class[]{String.class, int.class}, Format[].class);
			getSupportedOutputFormatsMethod = getStaticMethodOnImplClass("getSupportedOutputFormats", new Class[]{String.class, int.class}, Format[].class);

		} catch (Throwable e)
		{
			implClass = null;
			
			logger.log(Level.SEVERE, "Unable to initialize javax.media.pim.PlugInManager: " + e, e);
			return false;
		} 
		
		return true;
	}

	private static Object callImpl(Method method, Object[] args)
	{

		try
		{
			return method.invoke(null, args);
		} catch (IllegalArgumentException e)
		{
			logger.log(Level.WARNING, "" + e, e);
			return null;
		} catch (IllegalAccessException e)
		{
			logger.log(Level.WARNING, "" + e, e);
			return null;
		} catch (InvocationTargetException e)
		{
			logger.log(Level.WARNING, "" + e, e);
			return null;
		}
	}
	
	public PlugInManager()
	{
		
	}

	public static Vector getPlugInList(Format input, Format output, int type)
	{
		if (!init())
			return null;
		return (Vector) callImpl(getPlugInListMethod, new Object[]{input, output, new Integer(type)});	
	}

	public static void setPlugInList(Vector plugins, int type)
	{
		if (!init())
			return;
		callImpl(setPlugInListMethod, new Object[]{plugins, new Integer(type)});	
	}

	public static void commit() throws java.io.IOException
	{
		if (!init())
			return;
		callImpl(commitMethod, new Object[]{});
	}

	public static boolean addPlugIn(String classname, Format[] in, Format[] out, int type)
	{
		if (!init())
			return false;
		return ((Boolean) callImpl(addPlugInMethod, new Object[]{classname, in, out, new Integer(type)})).booleanValue();	

	}

	public static boolean removePlugIn(String classname, int type)
	{
		if (!init())
			return false;
		return ((Boolean) callImpl(removePlugInMethod, new Object[]{classname, new Integer(type)})).booleanValue();	
	}

	public static Format[] getSupportedInputFormats(String className, int type)
	{
		if (!init())
			return null;
		return (Format[]) callImpl(getSupportedInputFormatsMethod, new Object[]{className, new Integer(type)});	
	}

	public static Format[] getSupportedOutputFormats(String className, int type)
	{
		if (!init())
			return null;
		return (Format[]) callImpl(getSupportedOutputFormatsMethod, new Object[]{className, new Integer(type)});	

	}
}
